A. Field of Invention
This invention pertains to the art of methods and apparatuses regarding vehicle window washer devices, and more specifically to apparatuses and methods regarding rear window washer fluid control devices.
B. Description of the Related Art
It is known to manufacture a vehicle that includes a rear windshield. Often, the rear windshield can be opened or lowered independent of a rear-facing door or tailgate. The opening or lowering of the rear windshield allows an operator to conveniently access the rear interior portion of the vehicle. Commonly, the rear windshield is used in combination with a rear wiper system. The rear wiper system may comprise a wiper arm that oscillates across the rear windshield in order to improve the vehicle operator's rearward field of view. Additionally, the rear washer system may allow the vehicle operator to selectively dispense or spray a fluid, commonly referred to as washer fluid, onto the rear windshield, in conjunction with the oscillation of the wiper arm, thereby increasing the effectiveness of the rear wiper system in various circumstances. Commonly, a single selector device comprising a combination switch, as is well known in the art, is used to selectively control the operation of the rear wiper system.
When an attempt is made to open or lower the rear windshield during operation of the rear wiper assembly, a control unit may cause the wiper arm to “force park” or move to a predetermined position, commonly referred to as a “parked position,” prior to causing the rear windshield to open or lower. The parked position may require the wiper arm to be positioned out of contact with the rear windshield such that the wiper arm will not impede the opening or lowering of the rear windshield. Upon movement of the wiper arm to the parked position, the control unit may then cause the rear windshield to open. Commonly, the control unit will cause the rear wiper arm to resume operating upon movement of the rear windshield back to the fully closed position.
Although known methods work well for their intended purpose, several disadvantages exist. Despite the wiper arm being disabled upon the occurrence of a predetermined condition, the rear wiper system is still able dispense or spray washer fluid. The use of a single selector device to control the operation of the rear wiper system frequently results in operator error during manipulation of the selector device. For example, an operator intending to cause washer fluid to be dispensed on the vehicle's front windshield may unintentionally manipulate the selector device in the wrong direction and instead cause washer fluid to be dispensed or sprayed onto the rear windshield. If the rear windshield is lowered or otherwise opened when the rear washer is erroneously selected, the dispensed washer fluid may enter the interior portion of the vehicle. Additionally, because the wiper arm is disabled or parked as a result of the rear windshield being opened or lowered, it may take an increased amount of time to detect the erroneous selection. The increased detection time may result from the vehicle operator hearing the associated washer pump operating combined with not seeing any washer fluid being dispensed onto the intended windshield. The increased detection time may result in an increased amount of washer fluid entering into the interior portion of the vehicle thereby increasing the amount of damage caused.
What is need then is a method and apparatus for preventing the dispensing of washer fluid onto the rear windshield when the rear windshield is not in a fully closed position.